| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.lucene.benchmark.quality.utils; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Objects; |
| import org.apache.lucene.index.FieldInfo; |
| import org.apache.lucene.index.StoredFieldVisitor; |
| import org.apache.lucene.search.IndexSearcher; |
| |
| /** Utility: extract doc names from an index */ |
| public class DocNameExtractor { |
| |
| private final String docNameField; |
| |
| /** |
| * Constructor for DocNameExtractor. |
| * |
| * @param docNameField name of the stored field containing the doc name. |
| */ |
| public DocNameExtractor(final String docNameField) { |
| this.docNameField = docNameField; |
| } |
| |
| /** |
| * Extract the name of the input doc from the index. |
| * |
| * @param searcher access to the index. |
| * @param docid ID of doc whose name is needed. |
| * @return the name of the input doc as extracted from the index. |
| * @throws IOException if cannot extract the doc name from the index. |
| */ |
| public String docName(IndexSearcher searcher, int docid) throws IOException { |
| final List<String> name = new ArrayList<>(); |
| searcher |
| .getIndexReader() |
| .document( |
| docid, |
| new StoredFieldVisitor() { |
| @Override |
| public void stringField(FieldInfo fieldInfo, String value) { |
| name.add(Objects.requireNonNull(value, "String value should not be null")); |
| } |
| |
| @Override |
| public Status needsField(FieldInfo fieldInfo) { |
| if (!name.isEmpty()) { |
| return Status.STOP; |
| } else if (fieldInfo.name.equals(docNameField)) { |
| return Status.YES; |
| } else { |
| return Status.NO; |
| } |
| } |
| }); |
| if (name.size() != 0) { |
| return name.get(0); |
| } else { |
| return null; |
| } |
| } |
| } |